From patchwork Wed Aug 19 03:36:22 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gui Jianfeng X-Patchwork-Id: 42512 Received: from hormel.redhat.com (hormel1.redhat.com [209.132.177.33]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n7J3bhhO031037 for ; Wed, 19 Aug 2009 03:37:43 GMT Received: from listman.util.phx.redhat.com (listman.util.phx.redhat.com [10.8.4.110]) by hormel.redhat.com (Postfix) with ESMTP id 953B9619D3C; Tue, 18 Aug 2009 23:37:42 -0400 (EDT) Received: from int-mx03.intmail.prod.int.phx2.redhat.com (nat-pool.util.phx.redhat.com [10.8.5.200]) by listman.util.phx.redhat.com (8.13.1/8.13.1) with ESMTP id n7J3bY7Z017202 for ; Tue, 18 Aug 2009 23:37:36 -0400 Received: from mx1.redhat.com (ext-mx04.extmail.prod.ext.phx2.redhat.com [10.5.110.8]) by int-mx03.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id n7J3bUFO026661 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 18 Aug 2009 23:37:31 -0400 Received: from song.cn.fujitsu.com (cn.fujitsu.com [222.73.24.84] (may be forged)) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id n7J3bHcb010440; Tue, 18 Aug 2009 23:37:18 -0400 Received: from tang.cn.fujitsu.com (tang.cn.fujitsu.com [10.167.250.3]) by song.cn.fujitsu.com (Postfix) with ESMTP id 3E34617003F; Wed, 19 Aug 2009 11:37:07 +0800 (CST) Received: from fnst.cn.fujitsu.com (localhost.localdomain [127.0.0.1]) by tang.cn.fujitsu.com (8.13.1/8.13.1) with ESMTP id n7J3i6O1005978; Wed, 19 Aug 2009 11:44:06 +0800 Received: from [127.0.0.1] (unknown [10.167.141.226]) by fnst.cn.fujitsu.com (Postfix) with ESMTPA id 49D07D40F0; Wed, 19 Aug 2009 11:41:10 +0800 (CST) Message-ID: <4A8B7336.7010800@cn.fujitsu.com> Date: Wed, 19 Aug 2009 11:36:22 +0800 From: Gui Jianfeng User-Agent: Thunderbird 2.0.0.5 (Windows/20070716) MIME-Version: 1.0 To: Vivek Goyal References: <1250451046-9966-1-git-send-email-vgoyal@redhat.com> <1250451046-9966-4-git-send-email-vgoyal@redhat.com> In-Reply-To: <1250451046-9966-4-git-send-email-vgoyal@redhat.com> X-RedHat-Spam-Score: 0.1 (RDNS_NONE) X-Scanned-By: MIMEDefang 2.67 on 10.5.11.16 X-Scanned-By: MIMEDefang 2.67 on 10.5.110.8 X-loop: dm-devel@redhat.com Cc: dhaval@linux.vnet.ibm.com, peterz@infradead.org, dm-devel@redhat.com, dpshah@google.com, jens.axboe@oracle.com, agk@redhat.com, balbir@linux.vnet.ibm.com, paolo.valente@unimore.it, jmarchan@redhat.com, fernando@oss.ntt.co.jp, mikew@google.com, jmoyer@redhat.com, nauman@google.com, m-ikeda@ds.jp.nec.com, lizf@cn.fujitsu.com, fchecconi@gmail.com, s-uchida@ap.jp.nec.com, containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, righi.andrea@gmail.com Subject: [dm-devel] Re: [PATCH 03/24] io-controller: Common flat fair queuing code in elevaotor layer X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.5 Precedence: junk Reply-To: device-mapper development List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com Vivek Goyal wrote: ... > + > +static void elv_preempt_queue(struct request_queue *q, struct io_queue *ioq) > +{ > + elv_log_ioq(q->elevator->efqd, ioq, "preempt"); > + elv_slice_expired(q); > + > + /* > + * Put the new queue at the front of the of the current list, > + * so we know that it will be selected next. > + */ > + > + requeue_ioq(ioq); > + ioq->slice_start = ioq->slice_end = 0; I think this assignment is redundant because these two members will be reset when this ioq is scheduled. Signed-off-by: Gui Jianfeng --- block/elevator-fq.c | 1 - 1 files changed, 0 insertions(+), 1 deletions(-) diff --git a/block/elevator-fq.c b/block/elevator-fq.c index d04e925..b3c387d 100644 --- a/block/elevator-fq.c +++ b/block/elevator-fq.c @@ -2650,7 +2650,6 @@ static void elv_preempt_queue(struct request_queue *q, struct io_queue *ioq) */ requeue_ioq(ioq); - ioq->slice_start = ioq->slice_end = 0; elv_mark_ioq_slice_new(ioq); } }